This invention relates generally to vehicle cab structures, and more particularly to a vehicle roll protective structure having improved sound attenuating roof and floor panels secured thereto.
Federal legislation imposes stringent limitations upon vehicle manufacturers relative to amount of noise and vibration levels transmitted into the operator area. Such rules and regulations are for the safety and comfort of the operator of the vehicle. It has been found, however, that the requirements of isolation for sound purposes and the rigidity for protection purposes tend to work against each other. In most general cases, resiliently mounting a member for sound insulation reduces the structural rigidity and strength of the member.
Roll protective frames and structures for vehicles are known in the art, as exemplified in U.S. Pat. No. 3,572,819, issued to James C. Moore; U.S. Pat. No. 3,632,134, issued to John H. Babbitt, Jr.; and U.S. Pat. No. 3,841,430, issued to John H. Babbitt, Jr. et al. These patents all provide structural rigidity for the safety of the operator and some sound attenuation.
However, it is a primary object of this invention to provide a vehicle roll protective structure having resiliently mounted floor and roof panels which will provide sound attenuation as well as structural rigidity.
A further object of the present invention is to provide a vehicle roll protective structure that is rugged and effective for operator protection, and provides for sound and vibration insulation for the comfort of the operator.
A still further object of this invention is to provide roof and floor panels for a vehicle roll protective structure which may be easily mounted and removed from the structure, yet complementing the structural rigidity of the roll protective structure when assembled thereto.